Palladium, chemistry, before and after uv light hits

Discussion in 'Alternative Processes' started by Mustafa Umut Sarac, Jul 25, 2013.

  1. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    I take palladium as example. What is the chemical when we brush the paper and what happens after uv hits ? Does uv disintagrates the chemical in to nanoparticles ? What is the size of the particles before and after the uv treatment ? How they become organized or does it a process happens and free from
    making groups ?

    And most importantly is there a way - may be quantum chemistry - to simulate the process per chemical molecule ?

    There is a free density functional theory nanoparticle software but I am in it for last couple of hours.
     
  2. cliveh

    cliveh Subscriber

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    That is some question.
     
  3. Ian Leake

    Ian Leake Subscriber

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    Palladiotype chemistry in the traditional process is fairly simple. The coating consists of ferric oxalate, sodium chloropalladite, a small amount of oxalic acid (which is usually included in the ferric oxalate solution) and water.

    Two things happen under UV light. Firstly, and most importantly, under UV the ferric oxalate is converted to ferrous oxalate. Later on (in the developer) this is used to form the palladium image.

    The second reaction under UV is that a small amount of sodium chloropalladite reacts with the oxalic acid, facilitated by moisture in the coating. This lays down a small amount of pure palladium to form the faint image that is visible after exposure but before development.

    The last important reaction is in the developer. The developer dissolves the ferrous oxalate which, once dissolved, is free to react with the remaining sodium chloropalladite to lay down the pure palladium image.

    Platinotypes have the same reactions, just substitute potassium chloroplatinite for the sodium chloropalladite. Mixing platinum and palladium is a little more complex, but the essentials are the same.
     
  4. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    Ian, Thank you very much.


    Is there any formula or curve to represent ferric oxalate to ferrous oxalate transition and ferrous oxalate dissolvement and play with palladium or platin ? There is lots of high end research goes on.

    And is there a ferrous oxalate alternative process alone.

    Umut